A method of rendering an image one or more pixels at a time in scanline order, wherein the image includes objects described by one or more levels, includes the steps of identifying at least one edge of the objects, with the at least one edge intersecting a first scanline, and building a compositing list for at least one identified edge. The compositing list includes levels that are activated on the first scanline at the identified edge and that contribute to at least one pixel on the first scanline in the rendered image. Additional steps include caching one or more of the compositing lists, wherein each cached compositing list is associated with a corresponding edge, checking, for a current edge intersecting a second scanline subsequent to the first scanline, whether the cached compositing list associated with the current edge is valid for the current edge on the second scanline, retrieving the cached compositing list if the checking step indicates that the cached compositing list is valid, and rendering one or more pixels on the second scanline using the retrieved compositing list.